--- a/eric6/Plugins/VcsPlugins/vcsMercurial/HgGraftDialog.py	Mon Mar 01 17:48:43 2021 +0100
+++ b/eric6/Plugins/VcsPlugins/vcsMercurial/HgGraftDialog.py	Tue Mar 02 17:17:09 2021 +0100
@@ -52,7 +52,8 @@
                  self.userEdit.text() != "")
             )
         
-        self.buttonBox.button(QDialogButtonBox.Ok).setEnabled(enable)
+        self.buttonBox.button(
+            QDialogButtonBox.StandardButton.Ok).setEnabled(enable)
     
     @pyqtSlot()
     def on_revisionsEdit_textChanged(self):